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A widely accepted tenant of galaxy formation theory is that red-and-dead galaxies maintain their quiescent status through the sustained impact of radio-mode feedback. Driven by an active galactic nucleus comma this feedback is purported to heat gas in the galaxy.s surroundings to prevent the accretion and cooling of gas onto the galaxy. Moreover comma radio-mode feedback drives gas outflows and may remove a substantive amount of gas from galaxies. While radio-mode feedback is now a nearly generic feature of numerical simulations of galaxy formation comma the physical mechanisms that drive the interaction between radio jets-lobes and gas in galaxies are still poorly known. With this proposal comma we will study a galaxy with bright radio jets (i.e. caught in the act) and therefore putatively exhibiting the radio-mode feedback that sustains its absence of star formation. Fortuitously comma a UV luminous quasar lies background to this galaxy with its sightline intersecting the system at an impact parameter R virgul 4 kpc. Existing optical spectra of the quasar shows likely CaII absorption associated with the foreground galaxy comma i.e. cool and dense gas. The proposed HST-COS observations will extend the analysis to a diverse set of diagnostics -- HI Lya comma OI comma SiII comma SiIII comma SiIV comma CII comma CIV -- to assess the metallicity comma kinematics comma and multi-phase nature of gas in the galaxy. These data will provide direct insight into the process of radio-mode feedback and offer tests for current and future models.